Kin 312-Preparing and Executing a Plan of Action

action preparation

involves the events that occur in the nervous system from the intention of an action to the initiation of an action; reaction time
-RT is an index of preparation required to produce an action

planning the action-cognitive level

1) Making the decision to act
o action preparation/planning begins with a decision or intention to act
--> act may be driven by internal goals OR response to environment
(ex: dart throwing=internal goal, softball/baseball=environment)

2) Developing a general plan
o how appropriate the action plan is for the situation is determined by:
-evaluation of the situation
-previous experience
(ex: volleyball--velocity of ball, where the ball is located, determines
whether to use 1 or 2 arms)

3) Adding details to the plan
o selecting various movement parameters (force, velocity, displacement)
o which body part will be used
o what environmental characteristics are present

task influences of preparation

-the number of response choices
-the predictability of the correct response choice
-influence of precue correctness
-stimulus-response compatibility
-foreperiod length regularity
-movement complexity
-movement accuracy
-repetition of a movement

the number of response choices

Hick's Law: RT= K log (N+1)
K= simple NRT
N= # of choices
(positive correlation betw. K and N)

the predictability of the correct response choice

as the predictability of one of the choices increases, RT decreases

influence of precue correctness

how you're looking at clues in the environment ahead of time
-50/50 chance of correct precue: NO preference
-80/20 chance of correct precue: bias toward higher probability

stimulus-response compatibility

RT will be faster if the relationship between the stimulus and response is compatible
ex: find volume button on remote
stimulus=buttons, compatibility=remote design

ex: open hinged door
stimulus=hinges, handle, etc.
compatibility? no

ex: STROOP EFFECT:
-say color of font; word "blue" written with blue color is said faster than the word "blue" written in yellow

foreperiod length regularity

if the foreperiod is the same for every simple RT task, RT will decrease
(ex: track and field gun)

movement complexity

RT increases as a function of the number of a component parts in a movement increases

movement accuracy

as the accuracy demand for a movement increases, the amount of prep time increases

repetition of a movement

if the same movement is required for many trials, the trials later in the sequence will have decreased RTs

Influence on the performer on initiation

1) alertness of a performer
-initiation time is reduced when the performer is alert and attentive
-ex: RT study warning v no warning (turn light on with a warning v turn the light on with no warning)

2) attentional focus
-RT is reduced when performers focus on a signal rather than a movement or set of movements

planning the action-neuromotor level

planning/execution of actions are associated with 4 areas of the CNS

1) limbic system
2) association cortex
3) projection system
4) spinal system

limbic system

-structure that surrounds the hypothalamus
-structures include: fornix, amygdala, hippocampus, cingulate, gyrus
-responsible for our intention to act according to environmental demands

association cortex

-distributed throughout the cortex
-act that is generated in the limbic system is analyzed and transformed into a general plan of action
-function: recognition, selection, and integration of relevant sensory input
-network of nerve pathways connect the limbic system and association cortex; decision to act or not to act is communicated

the projection system

-main function: determines how the action should be carried out; responsible for adding the movement dynamics to best fit the goal and environmental restraints
-consists of the sensory and motor areas of the cortex and other subcortical nuclei (basal ganglia, cerebellum, motor cortex)

spinal system

-regulates the timing of the muscle activation patterns; is the "fine tuner" of the systems
-information flowing within the systems is not unidirectional
-feedback loops between the system allow the CNS to make modifications
-these modifications are based on comparisons between the action produced and the goal action